It is known to form magnetoresistive random access memory (MRAM) structures using magnetic tunnel junction (MTJ) devices. By providing interconnected arrays of MTJ devices with their associated read and write lines, large MRAM arrays can be formed. Since large numbers of MTJ devices are often needed in such arrays, it is important to have a high manufacturing yield and optimum electrical properties. It has been found that the structures and processes used to form interconnected arrays of MTJ devices and their associated read and write lines are less than optimum. For example and not intended to be limiting, various insulating layers needed to separate the read and write lines (also referred to as local interconnects for read and bit and digit or program lines for write) from the MTJ devices must often be made thicker for processing yield purposes than is desired for electrical purposes, thereby adversely affecting electrical properties of the devices. Conversely, if such dielectric layers are thinned in order to improve the electrical properties of the devices, then manufacturing yield can be significantly degraded. Thus, there continues to be a need for improved MRAM structures employing MTJ devices and their associated read and write lines, especially for structures that can be easily manufactured with improved yield and electrical properties.
Accordingly, it is desirable to provide an improved MRAM and MTJ structure and method. In addition, it is desirable that the MRAM and MTJ structure and method be simple, rugged and reliable, and further, be compatible with semiconductor device and integrated circuit structures and fabrication methods, and preferably but not essentially adapted to be formed on the same substrate. It is further desirable that the improved MRAM and MTJ structure and method reduce or eliminate various process defect causes so that improved manufacturing yield may be obtained. Other desirable features and characteristics of the invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.